Autoimmune Diseases
Medical Background
The immune system is the body’s protective shield against infections. Autoimmune diseases occur when some of the body’s own cellular proteins are incorrectly recognized as “foreign” by immune cells (called T lymphocytes) and the body’s immune system attacks its own cells, organs and tissues. Common autoimmune diseases include Rheumatoid Arthritis (RA), Systemic Lupus Erythematosus (Lupus), Multiple Sclerosis (MS) and Type 1 diabetes (commonly called Juvenile Diabetes).
Rheumatoid arthritis is a chronic disease, mainly characterized by inflammation of the lining (or synovium) of the joints, which can also affect other organs. Joint damage occurs early in the onset of the disease, often with the first two years, and can lead to long-term joint damage that causes chronic pain, loss of function and disability.
At present, the cause of RA is not known, although genetic factors are believed to play a major role. There are drug treatments to reduce joint pain and swelling, relieve stiffness and prevent joint damage, and many people undergo surgery to repair damaged joints but there is currently no cure.
Lupus is a chronic, inflammatory, autoimmune disease that mainly affects women of child-bearing age. Its symptoms range from unexplained fever, swollen joints and skin rashes to severe damage of the kidneys, lungs or central nervous system.
The cause of lupus is not known. It is believed to be genetic, though environmental factors can play a role in triggering the disease. Drug therapy is used to help manage the symptoms of the disease, but the drugs themselves can diminish the overall quality of life.
For information about Multiple Sclerosis and Type 1 diabetes, please see the separate pages about those autoimmune diseases elsewhere in the “Diseases and Injuries” section of our website.
Human and Social Costs
Rheumatoid arthritis is one of the most serious and common forms of arthritis. An estimated 3 million Americans have the disease. RA occurs in all racial and ethnic groups, but over twice as many women suffer from RA than men. The onset of RA usually occurs in middle-age, although it often affects people in their 20s and 30s.
In addition to causing intense physical pain and joint deformities, RA often causes depression. It is estimated that 90 percent of those with rheumatic diseases will suffer depression during the course of their disease.
According to the Centers for Disease Control and Prevention, arthritis and related conditions cost the U.S. economy $86.2 billion per year in medical care and indirect expenses, including lost wages and production. In Missouri, the total cost is estimated at $2 billion a year.
Currently, about 1.5 million Americans have some form of lupus. Although the disease can affect people of all ages, 90 percent of all lupus patients are women who are stricken during their reproductive years ages 25 to 40. Lupus affects all ethnic groups, but it is two to three times more common and is frequently more severe in African Americans and Hispanics/Latinos. Studies show these groups also experience more complications of lupus, including both kidney failure and neurological problems.
Lupus can exact a terrible toll on patients’ internal organs by inducing chronic inflammation and scarring. Thirty to 50 percent of patients suffer from debilitating kidney damage, and only 50 percent of patients with organ threatening disease live 20 years past diagnosis.
Several studies suggest that the annual average cost to provide medical treatment for a person with lupus is between $6,000 and $10,000. For some people with lupus, however, medical costs may exceed several thousand dollars every month. Using an average annual cost of $6,000 to treat a person with lupus, the medical expenses due to lupus in the United States is $8 billion.
The Potential for Stem Cell Cures
More than 50 years of research on adult stem cells taken from adult tissues has produced such lifesaving treatments as bone marrow transplants for leukemia patients. Now, the new frontier in stem cell research involves early, or “embryonic,” stem cells (ES cells). Unlike adult stem cells, ES cells have the potential to turn into and regenerate any type of cell or tissue in the human body.
Research indicates that adult and ES cell research both have the potential to lead to new treatments for autoimmune diseases, such as lupus and rheumatoid arthritis.
For example, in a recent study by doctors at Northwestern Memorial Hospital in Chicago, hematopoietic (i.e., blood related) adult stem cells from the bone marrow of 50 lupus patients helped to reverse the course of the disease when transplanted back into the same patients.
However, the use of a patient’s own hematopoietic stem cells to treat autoimmune diseases is still experimental and has certain limitations and risks. There is a limit to the amount of bone marrow stem cells a patient’s body can generate and a risk that they could be rejected by the patient’s own immune system.
As explained on the National Institutes of Health excellent web page “Autoimmune Diseases and the Promise of Stem Cell-Based Therapies,” ES cells could provide alternatives that may avoid those problems. For example, because ES cells can turn into any cell in the human body, they could provide a way to generate and propagate unlimited numbers of hematopoietic stem cells outside the body. This would have a major impact on the safety, cost and availability of stem cells for transplantation.
Whether ES cells will provide advantages over donated cord blood or donated bone marrow stem cells remains to be determined. However, the current scientific evidence indicates that hematopoietic stem cells from umbilical cord blood or bone marrow have a more limited potential for self-renewal than ES cells.
Other evidence indicates that ES cells are considerably more receptive to genetic therapies than adult hematopoietic stem cells. This is significant because genetic therapies could someday be the key to developing cures for diseases that are believed to be caused or heavily influenced by genetic factors, such as autoimmune diseases.
At the University of Oxford, researchers have also successfully directed mouse ES cells to differentiate into dendritic cells (immune cells that “alert” and “switch on” other immune cells when “foreign” cellular proteins are detected). This research indicates that an ES cell-based approach might work in patients with rheumatoid arthritis. Longer-term follow-up and further characterization will be needed in animal models before researchers can proceed with the development of such an approach in humans.
As summarized by the National Institutes of Health, “Stem cell-based therapies offer many exciting possibilities for the development of novel treatments, and perhaps even cures, for autoimmune diseases…Ultimately, the potential to alleviate these devastating chronic diseases with the use of stem cell-based technologies is enormous.”
That’s why the overwhelming majority of medical experts, medical organizations and patient groups agree that all types of stem cell research should be pursued in the effort to find cures for autoimmune diseases like RA, lupus, MS and Type 1 diabetes.
And, that’s why both adult and ES cell research are strongly supported by major medical and patient advocacy organizations like the American Medical Association, American Academy of Neurology, American Neurological Association, American Diabetes Association, Juvenile Diabetes Research Foundation International and National Multiple Sclerosis Society.
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